A touch screen is known from DE 201 02 197 U1, for example. DE 201 02 197 U1 discloses a touch screen for the visual display of electronic signals and confirmational touch input of characters and symbols comprising a function level for the visual display and key input and a corresponding, higher-level, selectively deformable protection level. DE 602 20 933 T2 discloses a method for distinguishing between two or more temporally overlapping pieces of touch information in a touch screen system. US 2006/0161871 A1 discloses an input/output platform which has an input/output interface having one or more input/output devices. Furthermore, a proximity system for detecting whether there is a finger in the close surroundings of the input/output interface without touching it is provided.
EP 1 517 228 A2 discloses a method for gesture recognition, wherein an image is presented on a touch surface, wherein a touch of this contact face is detected and it is ascertained whether multiple touches correspond to a gesture, the image presented being altered when a particular gesture is recognized.
U.S. patent application Ser. No. 11/928,629 dated Oct. 30, 2007 describes a motor vehicle having a touch screen arranged in a passenger compartment of the motor vehicle for the output of an output signal which is dependent on a touch of the touch screen and having a control arrangement for evaluating the output signal for the purpose of handwriting recognition for the recognition of a text in a language based on an alphabet, a language based on syllabary and/or a language based on graphic characters.
WO 2009/007704 A1 discloses a touch panel having a plurality of sensor elements which are distributed over the face of the touch panel, wherein a capacitance measuring circuit is connected to the sensor elements in order to obtain capacitance signals. On the basis of these capacitance signals, the coordinates of touches of the touch panel are ascertained.
US 2009/0284491 A1 discloses a matrix-based touch screen for detecting multiple touches.
US 2008/0309629 A1 discloses a method for processing areas which are identified when a touch screen is touched on the basis of a plurality of pixels which have touch values from a touch sensor panel, wherein pixels which have touch values which indicate no touch are removed. By contrast, pixels which are not removed are processed using a watershed algorithm.
US 2008/0158145 A1 discloses a method for processing values from a touch screen (touch sensor device). This involves the production of an image which is segmented for the purpose of identifying a plurality of touch areas.
US 2009/0095540 A1 discloses a method for classifying an input for a multitouch sensitive digitizer. This involves the identification of a plurality of discrete regions and the determination of a relationship between at least two regions.